Australia's competition watchdog has launched an investigation into the country's honey industry. It follows tests that revealed that almost half of the honey in shops was adulterated and unwittingly sold as Australian. Food fraud is a multi-billion-dollar global problem - and one that researchers are trying to combat with technology. Greg Navarro has more.

For the last 2 years, Craig Heragthy has been working to help food producers to keep their word.

CRAIG HERAGTHYNATIONAL AGRIBUSINESS LEADER, PWC AUSTRALIA "The ability to honour the promises that they wish to make directly to the consumers that they are selling the product to."

Those promises are becoming increasingly harder to keep as a result of food fraud leaving consumers with something other than what they thought they were paying for.

CRAIG HERAGTHY NATIONAL AGRIBUSINESS LEADER, PWC AUSTRALIA "The most prominent type that we see is just the straight substitution so it could be the same species or it could be the same product but swapping out a high quality product for an inferior one to make that margin."

Food fraud is a multi-billion dollar criminal industry. In 2016, Europol seized more than 100,000 tons of counterfeit products from more than 60 countries - including olives painted with copper sulphate and monkey meat. The impacts from that fraud can also be deadly. In 2008, milk powder tainted with melamine killed 6 infants and sickened hundreds of thousands more in China. And in many cases, experts say food fraud in commonly sold items goes undetected.

KAREN CONSTABLEPRINCIPAL CONSULTANT, FOOD FRAUD ADVISORS "If you look in your shopping trolley and you have got 100 products in there you have got maybe 10 that have been affected in some small way."

GREG NAVARROSYDNEY "That means when it comes to the food in your fridge, there is no reliable way for you the consumer to tell whether it's real or fake."

Heraghty has focused his attention on Australia's beef industry which has built a global reputation for exporting high end, quality meat.

"Effectively the particles themselves are just - and away you go."

He's testing a method of spraying meat with a silicone dioxide marker that's invisible to the eye.

"The unique waves that have been etched inside the particle come back into the light, give you the number, the unique wave length."

That information allows consumers to verify what it is that they are buying.

CRAIG HERAGTHY NATIONAL AGRIBUSINESS LEADER, PWC AUSTRALIA "Where it came from, how it was processed, does it have hormones, does it not have hormones?"

Heragthy is confident that the technology is relatively tamper proof, and will help arm producers against fraud. It will initially be used on packaging and is expected to be available by the end of the year. Greg Navarro, CGTN, Sydney.